Work clamp for buttonhole-sewing machines



Dec. l1 1923. 1,477,142

M. MccANN WORK CLAMP FOR BUTTONHOLE SEWING MACHINES Filed July 8. 1922 Patented Dec. 1l, 1923.

UNITED STATES PATENT OFFICE.y

IIOBAEL HGCANN, OF GLENMORRIS, NEW YORK, ASSIGNOB '.lO FREDERICK OSANN COIPANY, OF NEW YORK, N. Y.,

A CORPORATION OF NEW YORK.

WORK CLAMP FOB BUTTONHOLE-SEWING MACHINES.

Application led .Tnly 8, 1922. Serial No. 573,650.

To all 'whom zt may concern.' p

Be it known that I MICHAEL MCCANN, a citizen of the United States of America, residing in Glenmorris, Long Island, in 5 the county of Queens and State of New York, have invented certain new and useful Improvements in Work Clamps for Buttonho1e-SeWing Machines,4 of which the following is a true and exact description, reference being had to the accompanying drawin which for'n a part thereof.

y invention relates to Work clam s for button hole sewing machines and has or its object to rovide a clampin device for holding the c oth in which the utton hole is to be formed with great security and under the best possible conditions as to stretch for the formation of the button hole.

The nature of my improvements will be best understood as described in connection with the drawings in which they are illustrated and in which Fi re 1is a side elevation of a portion of a utton hole sewing machine including the work holding` clamping mechanism.

Figure 2, a cross sectional view on the line 2-2 of Fig. 1. Figure 3 is a view similar to Fig. 2, but with the clam mechanism shown closed down in work Iliolding osition.

Figure 4 is a longitu inal section on the line 4 4 of Fig. 3.

Figure 5 is a plan view of the needle late.

Figure 6, a perspective view of the ower cla-mp member. y

Figure 7 a perspective view of the upper clamp member shown in reversed position, and

Figure 8 is a view on the line 8--8 of is the housing or casing of the machine, A indicating the usual opening through the top plate of the casing for the passage of the needles and A2 the overhanging arm of the machine carrying the needles indicated at A". B is the needle plate of the machine having openings as indicated at B and B2 for the passage of the needles and a longitudinal slot indicated at B for the passage of the knife which cuts the button hole and on each side of the knife slit and needle passages I have formed arallel grooves indicated at B4 B4. C indicates the clamp holdmg slide moving, as is common in such machines, in guideways formed on the top of the machine casing, and extending forward from this slide C and over the needle plate. B is the lower clamp member D in which is formed the opening D' over which the portion of the cloth J in which the button h'ole is to be formed is stretched, and at eachend of this o ening D' are formed the transverse slots indicated at D2 andDs separated from the opening Dby the cross bars D* D4. E 1s an arm carrying the upper clamp member and pivoted to the silde C as indicated at E, the clamp member indicated at H being preferably carried, as shown, on an elastic arm E2 attached to the arm E. The arm E and the clamp member attached to it are normally pressed down with a proper elastic ressure, as shown, by a spring F2 surroundlng a rod F and resting on the top of the frame E, the tension of the sprin being adjusted by a nut indicated at The frame E and the upper clamp member can be raised by an convenient mechanism. As shown, a rod attached to the under side of the arm E extends through a slit in the top plate of the machine casin into operative registry with the finger secured at one end of the lever G pivoted at Gr2 and having an end Cr4 which extends through an opening in the side of the casing and is usually connected by a chain with a treadle.

The upper clamp member H is formed with acentral openin y H to expose the portion of the cloth J 1n which the button hole is to be formed and on each side of this opening I provide downwardly extending bars indicated at H2 H2 placed so as to enter the opening D in the member D in fairly close relationship to the edges of this opening and preferably and, as shown, to extend down into the grooves B of the needle plate. At the end of the opening H I form downwardly extending bars H", H, placed so as to enter the opening D in fairly close relationship to the cross bars D and I also provide the upper clamp member with 100 l downwardly extending cross bars H, H,

on to the needle plate and over the ends of located so as to register with and extend down into the slots D2, D, and by preference, bars H2, Ha and H are serrated so as to take a better grip on the cloth.

In operation, the upper clamp member being -in elevated position Vand the lower .clamp member resting on the needle plate,

as shown in lFigures, 1 and 9., the cloth is inserted between the upper and lower clamp members and the upper clamp member permitted to move downward with the result that the longitudinal bars H2 press the cloth pressed on the needle plate; at the same time the cross bars Ha H3 press the cloth down the opening D and the cross bars H4, H4, press a bight of the cloth down into the grooves D2, D, with the result, as is of course obvious, that the cloth is very ositively and rigidly held between the c amp members at each end of the portion in which the button hole is to be formed and also firmly pressed against the needle plate over which it is moved by the clamp.

The advantages of my improved clamping mechanism will be readily recognized by all skilled in the art and while I believe that the construction illustrated and above described is the best form in which my invention can be embodied it will be quite obvious that certain features of my new and improved clamp can be used with advantage apart from others. I do not wish to be understood as limiting my claims tothe specific construction except in so far as the different features thereof are expressly called for in the claims.

Having now described my invention, what I claim as new and desired to secure by Letters Patent, is:

1. A work clamp for button hole sewing machines comprising a lower member having a recess over which the portion of the cloth in which the button hole is to be formed extends, two parallel cross bars one at each end of said recess and slots formed in the member outside of said bars in combination with an upper clamp centrally recessed to expose the goods and having downwardly extending bars adapted to enter the slots in the lower member.

2. A work clamp for button hole sewing machines comprising a lower member having a recess over which the portion of the cloth in which the button hole is to be formed extends, two parallel cross bars one at each end of said recess and slots formed in the member outside of said bars in combination with an upper clamp centrally re- .at each end of said recess and slots formed in the member outside of said bars, in combination with an upper clam centrally recessed to expose the goods an having transversely lying downwardly extending bars iagdapted to enter the slots in the lower mem- 4. A work clamp for button hole sewing machines comprising a lower member having a recess over which the portion of the cloth in which the button hole is to be formed extends, two parallel cross bars one at each end of said recess and slots formed in the member outside of said bars, in combination with an upper clamp centrally recessed to expose the goods and having transversely lying downwardly extending bars adapted to enter the slots and the ends of the recess in the lower member.

5. A work clamp for button hole sewing machines comprising a needle plate having parallel grooves formed in its upper face, in combination with a lower clamp member moving backward and forward over the needle plate in a line parallel to the grooves and formed with a recess over which the portion of the cloth in which the button hole is to be formed extends and an upper clamp member recessed to expose the clot-h and having longitudinal bars extending down along the sides of the recess in the lower member into the grooves in the needle plate.

6. A work clamp for button hole sewing machines comprising a needle plate having arallel grooves formed in its upper face, 1n combination with a lower clamp member moving backward and forward over the needle plate in a line parallel to the grooves and formed with a recess over which the portion of the cloth in which the button hole is to be formed extends and with transversely extending slots separated from the recess by cross bars, and an upper clamp member recessed to expose the cloth and having transverse bars extending down into the slots and longitudinal bars extending down alon the sides of the recess in the lower mem er into the grooves in the needle plate.

7. A work clamp for button hole sewing machines comprising a needle plate having parallel grooves formed in its upper face, in combination with a lower clamp member moving backward and forward over member recessed to expose the cloth and the needle plate in a line parallel to the having transverse bars extending down on grooves and formed with a recess over which each side of the cross bars and longitudinal l0 the portion of the cloth in which the butbars extending down along the sides of the ton hole is to be formed extends and with recess in the lower member into the grooves transversely extending slots separated from in the needle plate.

the recess by cross bars and an upper clamp MICHAEL MGCANN. 

